A dual clutch transmission, or DCT, generally implements one clutch for the odd numbered gear ratios, and a second clutch for the even numbered gear ratios such that there is no torque interruption during a ratio change. A “torque interruption” refers to a period during a ratio change wherein the engine is decoupled from the drivetrain so that there is no torque being transferred to the wheels.
The two clutches in a dual clutch transmission are typically either wet or dry clutches, and may be either axially stacked or radially stacked. Dry clutches may be more efficient and less expensive in some applications than a wet clutch. Radially stacked dual clutch transmissions offer packaging advantages over axially stacked dual clutch transmissions. As an example, vehicles requiring a short transmission, such as front wheel drive vehicles, cannot practically package an axially stacked dual clutch configuration.